Pulmonary hypertension

What is pulmonary hypertension?

Pulmonary arteries

The pulmonary artery carries blood from the right side of the heart to the lungs. Pulmonary hypertension occurs when there is high pressure in this artery.

The pressure in the pulmonary arteries is higher when a baby is born, but it usually lowers over the next few hours or days. When the pressure stays high, it is called persistent pulmonary hypertension of the newborn and is usually treated successfully in hospital.

Symptoms of pulmonary hypertension

Pulmonary hypertension is very rare in children, but it is serious. Because it is so rare, it can go undiagnosed for a long time. Symptoms may include decreased exercise tolerance, shortness of breath, chest pain and fainting or near fainting.

Cause of pulmonary hypertension

Pulmonary hypertension may appear on its own and it is not clear what causes it. This kind of pulmonary hypertension is usually called idiopathic.

There are other conditions that may result in pulmonary hypertension, for example:

• it may be associated with congenital heart disease
• chronic lung disease
• structural abnormalities of the lungs or lung vessels
• blood clots in the lung vessels
• sleep disorders
• chronic exposure to high altitude
• it may be drug and toxin induced

Diagnosis of pulmonary hypertension

The doctor will take your child's medical history and do a physical exam. Then the doctor will do an electrocardiogram, chest X-ray and echocardiogram. Other tests may be necessary.

Heart catheterization is the best test to confirm the diagnosis and assess how severe the condition is. It also lets the doctor give drugs during the procedure to see if the pressure in the pulmonary artery can be lowered.

Treatment of pulmonary hypertension

Treatments for pulmonary hypertension are aimed at relieving symptoms. They include:

• oxygen to lower lung pressure to help the child breathe more easily
• drugs called diuretics to get rid of extra fluid in the body
• specific drugs given by mouth such as sildenafil (Revatio), bosentan (Tracleer) or macitentan (Opsumit), or prostacyclin type medication (Flolan, Remodulin, Uptravi) which may be given as a continuous infusion. These medications may lower the pressures in the pulmonary artery.

Pulmonary hypertension is a challenging condition to treat. However, the good news is that treatments have become available that can slow down the disease, or even help reverse the damage to the lungs.

In rare cases, children with pulmonary hypertension have needed a lung transplant.

Long-term problems caused by pulmonary hypertension

Pulmonary hypertension can lead to various problems:

• The right ventricle of the heart needs to work harder to pump blood to the lungs. This makes the right side of the heart get bigger. In the long term, it can lead to heart failure.
• When the arteries are under high pressure for a long time, tissue in the arteries becomes stiff. As the disease goes on and the high pressure continues, the blood vessels get scarred. This makes them weak and at risk of tearing.
• The condition can also lead to abnormal heart rhythms because the right ventricle is stretched.

What is Eisenmenger's syndrome?

Eisenmenger's syndrome, is pulmonary hypertension resulting from a heart defect. Generally, it begins with a heart defect such as ventricular septal defect (VSD). Extra blood flows to the lungs through the VSD. Over time this causes high pressure in the lungs. Once the lung pressures are high enough the blood flow through the heart reverses. The high pressure causes the blood flow through the VSD in the heart to reverse and go from the pulmonary arteries to the body. Because this blood has not yet travelled to the lungs, it is "blue blood" and may cause cyanosis.

Eisenmenger's syndrome can develop in early childhood or take time to develop over the years. Symptoms are similar to those listed above, together with the appearance of cyanosis.

Once Eisenmenger's syndrome is diagnosed, it is too late to correct the VSD. Treatment involves the use of drugs to control symptoms and prevent the condition from getting worse.